Automatic train control



J. S. CRAWFORD.

AUTOMATIC TRAIN CONTROL.

APPLICATION FILED DEC. 26, 1917.

1,362,927, Patented Dec. 21, 1920.

2 SHEETSSHEET l.

INVENTOR JOHN S. CRAWFORD flit/tam ATTORNEY J. S. CRAWFORD.

AUTOMATIC TRAIN CONTROL.

APPLICATION FILED 05c. 26. 191?.

1,362,927, Patented Dec. 21, 1920.

2 SHEETS-SHEET 2.

WULM W \JOHN S. CRAWFORD shutting UNITED STATES PATENT oFFica JOHN s. CRAWFORD, or NEW LoNnoN, CONNECTICUT.

AUTOMATIC TRAIN CONTROL.

To all whom it may concern:

Be it known that I, JOHN S. CRAWFORD, a citizen of the United States of America, residing at New London, Connecticut, have invented a new and useful Automatic Train Control, of which the following is a specification.

This invention "relates to the automatic control of railway trains, and has for its objects the provision of reliable and. eificient mechanism for automatically controlling a train in the presence of danger conditions.

Special objects are to provide simplified and improved mechanism for automatically oil the power and applying the brakes.

' Another important object is to bring about both service and emergency applications, of the brake to meet existing conditions.

*The invention is designed to be applied to and used in conjunction with the usual air brake systems and briefly stated comprises a control valveadapted to be operated by a so-called cam or obstruction provided on the trackway and'which when so actuated permits pressure from the train pipe to actuate a valve for shutting oil communication between the main reservoir and engineers valve, said train pipe air being ther'eby vented to bring about an application of the brakes. This shut-off valve when so actuated serves to open up a flow of fluid under pressure from the main reservoir to a pressure operated power controlling member, and also provides for a flow of actuating fluid to restore'the control valve to its original condition.

Other features of the invention are a special cut-off valve for rendering the automatic system inoperative when the engineer is exercising the proper control over the train, an automatic pressure control valve for effecting the proper application of the brakes, and special electro motor mechanism for operating the cam or track device.

' Other features of the invention will appear as the specification proceeds, attention being now directed to the accompanyv 7 Figure 1 is a more or less ing drawings which illustrate the invention embodied in a practical working form.

In said drawings diagrammatic representation of my automatic control sys- Specification of Letters Patent.

' tem as applied to a steam railway, the several parts of the apparatus being for the most part shown in section tobetter illustrate thGII COIlStIHCtlOIL and operation.

- Fig. 2 is a cross sectional view of the serv-- Patented Dec. 21, 1920. Application filed December 26, 1917. Serial No. 208,779. L

Fig. 6 is a fragmentary sectional View of a part of a compensating or automatically adjusting valve.

The numeral 7 designates the train pipe or train line of a typical air brake installation, 8 indicating the main reservoir and 9 the engineers valve of such system, said' engineers valve being disposed as usual In a plpeconnect on 10 between the 'main reservoir and train pipe. 11 designates the' power controlling member, which in the case of a steam railway is illustrated in the form of a throttle lever.

The control valve is indicated at 12 and the shut-off valve is indicated at 13.

Specificallythe control valve comprises i in the present disclosure a cylinder 14 within which there is mounted a valve piston 15 controlling an inlet 16 and anoutlet- 17, said piston being mounted on a protruding piston rod 18 carrying a roller 19 at its lower end for engagement with the track cam. This latter element is designated 20 and maybe in the form of a short rail sec-- tion or ramp disposed between the tracks inposltion to engage when raised with the trip roller 19.

The cam or tripping device is actuated in the present illustration by an electric motor comprising an armature element-21 mounted on a vertically reciprocating plunger 22 and working within a relatively stationary field magnet structure 23. The cam is. mounted on-the upper end of the plunger 22 and this vertically reciprocating structure may be counter-balanced by a weight .24 adjustably engaged on the end of a pivoted lever 25 which is shown pivotally engaged with the lower end of the plunger;

The electrical connections, as will later be pointed out in detail, are such that atone time the armature and field will be energized to attract one another and under reverse conditions will be energized to repel each other.

The main shut-off valve'13, as here disclosed, consists of a cylinder 26 within which works a piston 27 carrying a valve 28 for engagement with a valve seat 29, the latter being disposed'in a passage forming part of the connections between the main reservoir and engineers valve. The shut-off valve piston 27 also controls a vent 30 to atmosphere.

wardly opening communication between the inlet and outlet ports 16-17 and permitting a flow of air from the train pipe through pipe 32 to the head of the actuating piston 27 of the shut-01f valve. This piston will be thereupon actuated to carry the valve 28 to its seat thereby cutting 01f communication between the main reservoir and engineers valve. The piston in this movement uncovers the vent 30 thereby permitting the train pipe air to escape byway of said vent, this resulting in an applicationof the brakes.

The force for cutting ofi' the steam or othenpower is supplied in my present disclosure from the main reservoir through pipe 33 by-passed around the shut-off valve and under the control of a valve 34 which in turn is under the control of the shut-ofi' valve. This air supply valve 34 is shown directly connected with a piston 35 working in a cylinder 36 which latter may be made as an integral part of the main shutoff valve. the head of the piston therein is connected by a port 37 with the shut-off valve passage 38 so that when the shut-off valve is open, as it is under normal running conditions, valve 34 will be held closed by the main reservoir pressure on top of piston 35. When however the shut-off valve is actuated as above described, to close off communication between the main reservoir and engineers valve, the port 37- will be covered by the'stem portion 39 of valve 28 and pressure on top of piston 35 will be thereby removed. The remaining pressure on top of piston 35 is vented at such times by way of a vent port 40 provided in the cylinder above the piston and connected by piping 41 with a ,port 42 opening into the cylinder 26. This port 42 is normally covered by the piston 27 but. when said piston is moved over The top of cylinder 36 above as above described to close the shut-01f valve, said port is opened and the pressure on top ofcylinder 35 can thereby escape through piping 41 and port 42 out the then-opened vent 30.

When the shut-01f valve has been close and the pressure on top of piston 35 thus relieved, the air supply valve 34 opens under influence of the main reservoir pressure supply beneath the same through piping 33 and permits flow of airat said reservoir pressure through port 43 and by way of piping 44 to a point beneath the piston 45 in the throttle closing cylinder 46. This piston is connected by a piston rod 47 with the rearward end of the pivoted throttle leverso 'as to impart a closing movement to the throttle. I

To enable this closing movement the throttle latch must be released and this is accomplished in the case illustrated by a throttle lifting piston 48 connected with the latch rod 49 and working in a cylinder 50, said cylinder being supplied with actuating fluid through branch piping 51 connected with the supply pipe 44. A swivel joint is provided in this branch line to allow for the pivoting movement of the throttle lever, said joint comprising a chambered member 52 mounted on the throttle, to which the piping leading to the latch lifting cylinder is connected and which is provided with a passage 53 concentrio with the pivotal axis of the throttle in which is rotatably engaged the end of the branch piping 51 leading from the supply 1 pipe 44. 1

In the present illustration the control is exercised from the track signals by means of switches operated by the semaphore arm and controlling operation of the cam lifting mo- 105 tor; 54 designates the semaphore or track signal carrying a control arm 55 supporting a series of switch contacts 56, 57 and 58 for bridging contacts 5960; 6162; 6364 respectively. Contact 59 is connect- 110 ed-by wiring 65 with the contact 66 within the housing 67 of the track motor, said contact being slidingly engaged by a brush 68 carried by the movable element of the motor and connected by wiring 69 with the arma- 115 ture 21.' Contact 60 is connected by wiring 70 with one side of the stationary field winding23' and contact 61 is connected by wiring 71 with the other side of this field winding. Contact 62 is connected by wiring 72 with one of the current supplying wires 73. Contact 63 is connected by wiring 74 with a contact 75 with which engages the sliding contact 76, connected with the other side of the armature. Contact 64 is connected by wiring 77 with the other line wire 78.

. When therefore the semaphore arm stands in the warning position shown in Fig. 1, the circuits will be established as follows: from line wire 73 through wiring 72, contact 62,

bridging contact 57, contact 61, wiring '71 through field winding 23 and by way of wiring 70 to contact 60, bridging contact 56,

follows for effecting a reverse operation of the motor; bridging contacts 80, 81, 82 on the semaphore operated arm 55 connect con-' tacts 83-84; 8586 and 87-88 respectively. Under such conditions current flows from, the line wire 73 through wiring 89 to contact 86 across bridging contact 81 to contact 85 and thence by wiring 90-71 to the first side of field winding 23, and by way of Wiring 70-91'to contact 84 acrossbridging contact 80 to contact 83 and by way of wiring 92-7 4, contact 75, brush 76 and connection 79 to the opposite or reverse side of the armature 21 and thence by Wiring 69, brush 68, contact 66 and wiring 65-93 to contact 87 and across bridging contact 82 to contact 88 and thence by wiring 94 to the return side 78 of the line. Under these socalled safety conditions the armature and The counter-balance weight 24 is usually so adjusted that in case of any electrical connections being broken, the cam will be automatically elevated.

The control valve 12 is designed to effect a service application of the brakes. When therefore said valve is operated by the cam elevated as just described, said valve will release the train pipe air at a rate such as to efiect a so-called service brake application. This is accomplished by providing what I have termed a compensating or automatically adjusting valve 95 in the air connections between the train pipe and control valve. This compensating valve comprises a piston 96 Working in the cylinder 97 and normally acted upon by the train pipe air, said piston carrying a slide 98 having a substantially diamond-shaped valve port 99 therein controlling a port 100 connected by the piping 31 with the control valve. When the full pressure train pipe air is upon piston 96, the piston will be forced downward so that the constricted upper end of the diamond-shaped valve port 99 will be disposed over the outlet port 100. Consequently, with the train pipe air at normal pressure, when the control valve is actuated the escape of train pipe air by way of cylinder 26 and vent 30 will at first be restricted to prevent too sudden an application of the brakes. Then, as the train pipe pressure is reduced by the venting thereof, the

piston 96 in the compensating cylinder will rise under the action of the counter-balance spring 101, carrying the diamond-shaped trol valve will be restored to normal operative position along with the shut-off of power. After operation of the automatic stop mechanism the engineer may regain control of his train by opening the shut-off valve to again establish communication between the main reservoir and engineers valve, this being accomplished by returning the shutoff valve to the position indicated in Fig. 1 by forcing in'the handle 103 connected with the shut-off valve. Vhen this is done air under reservoir pressure is again applied to, the top of piston 35 which closes the air. supply valve 34. The air from the throttle unlatching cylinder and, control valve cylinder 14 in this case vent back through the pipe 44, port 43 and by way of an exhaust port 104 and vent pipe 105 into the cylinder 26 at 106 in front of piston 27 and thence out the vent -30. v

To prevent duplication of the engineers actions the automatic stop is automatically 105 cut out of operation when the train is properly controlled by the engineer. Thus when the engineer, observing the signals set against him, reducesspeed by applying the brakes, pressure in the train pipe is reduced and this effect is taken advantage of to render the automatic stopping mechanism inoperative. The means for this purpose here comprises a cut-out cylinder 107 interposed in the line of connections between the train pipe and control valve and having a spring pressed piston 1'08 therein acting as a valve to control the passage 109 between the said cylinder and the compensating cylinder. The train pipe air, connected by piping 110 with the head of the cylinder 107 forces said piston 108 over to open up communication between the train pipe and control valve by way of port 109. When however. the pressure in the train pipe is reduced by the engineers application of the brakes said piston 108 is moved over by its counter-balance sprmg to close the port 109 andthus cut ofi communication between the train pipe and control 1 0- valve. The operation of thecontrol valve then will have no effect upon the system. VV'hen piston 108 thus moves over under the influence of its spring to close passage 109,

provided with a valve rod 115 carrying a a roller 116 on its lower end for engagement with a so-called danger or emergency stop 'cam. This latter cam will be off-set to one side of the service stop cam, already described, and means similar to those described in connection with the service stop cam will be provided .for operating the same. The emergency stop control acts when operated to provide for a sudden release of the train pipe pressure to thus effeet an emergency application of the brakes. This is accomplished in the illustration by connecting cylinder 113 directly with the train pipe by a connection 117 and with the pipe 32 by connection 118, so that when said emergency valve is operated the full train pipe pressure will be quickly vented by way of vent 30 of the shut-off valve.

The service and emergency stop control valves maybe coupled together in a single unit as indicated in Figs. 2, 3. Said valves may be separately tested before starting on a run by means of a test valve 119 which may be turned in opposite directions to provide flow through either pipe 120 or 121 to lift either one of the valves, pressure being supplied for this purpose by piping 122 connected with the main reservoir. Check valves 123 maybe provided in these test connections 120, 121 to prevent escape of train pipe air by way of these connections when the control valves are operated by the track trips. g

The track motor which I have provided is particularly simple and sturdy in construction and therefore well adapted to the uses for which it is designed. There is practically only one moving part, that is, the movable armature structure and the parts are all protected Within the housing shown. As a further protection, .the armature structure may be covered by a bellshaped dome or hood 124 carried by the plunger 22 and covering the armature and field and the sliding electrical connections described. By adjusting the weight 24 the motor'may be set to operateas desired.

The invention it will be seen is capable of ready application to the train controlling and braking systems of trains now in use and it will be seen that on the whole combination with the main reservoir, train pipe and engineers valve of an air brake system, a control valve adapted for operation by a member on the track-way, a main shut-off valve between the main reservoir and engineers valve, air connections from the train pipe to the control valve and from the control valve to the main shut-off valve for actuating the latter upon operation of the control valve, a vent for said train pipe airopened by said shut-off valve upon actuation of the same as aforesaid, a pressure actuated member for returning the control valve to its original condition, valve mechanism under control of the shut-off valve and air connections therefrom to the control valve returning means.

2. An automatic train stop, comprising in combination with the main reservoir, train pipe and engineers valve of an air brake system, a control valve adapted for operation by a member on the track-way, a main shut-off valve between the main reservoir and engineers valve, air connections from the train pipe to the control valve and from the control valve to the main shut-ofi valve for actuating the latter upon operation of the control valve, a vent for said train pipe air opened by said shut-off valve upon actuation of the same as aforesaid, a pressure actuated member for returning the control valve to its original condition, air connections from the main reservoir to the control valve returning means and valve mechanism in said air connections under'control of the shut-oil valve.

3. An automatic train stop, comprising in combination with the main reservoir, train pipe and engineers valve of an air brake system, a control valve adapted for operation by. a member on the track-way, a main shut-off valve between the main reservoir and engineers valve, air connections from the train pipe to-the control valve and from the control valve to the main shut-off valv for actuating the latter upon operation 0 the control valve, a vent for said train pipe air opened by said shut off valve upon actuation of the same as aforesaid, a pressure actuated member for returningthe control Valve to its original condition, valve mechanism under control of the shut-01f valve and air connections therefrom to the control valve returning means, a power controlling member, fluid pressure operating means for operating said member and fluid pressure supply connections to said member under the control of the shut-ofi valve.

4;. An automatic train stop comprising in combination, a main reservoir, a train pipe, an engineers valve between the main reservoir and train pipe, a control valve arranged to be operated by a member on the trackway, a shut-off valve for closing the connection between the main reservoir and engineers valve, connections from the train pipe to the control'valve and from the control valve to the shut-off valve for operating said shut-ofl valve when the control valve is actuated, a vent for said train pipe air opened by said shut-off valve when the same is actuated by said train pipe air and an automatic cut-out valve interposed in the connections between the train pipe and control valve for'rendering the control valve inoperative when the train pipe pressure is reduced by the manual control of the brakes.

5. An automatic train stop, comprising in combination, a main reservoir, a train pipe, an engineers valve between the main reser voir and train pipe, a control valve arranged to be operated by a member on the track way, a shut-ofi' valve for closing the connection between the main reservoir and engineers valve, connections from the train pipe to the control valve and from the control valve to the shut-01f valve for operating said shut-off valve when the control valve is actuated, a vent for said train )ipc air opened by said shut-01f valve when t ie same i actuated by said train pipe air, and an automatic pressure controlling valve interposed in the connection between the train pipe and control valve for automaticallv controlling the flow of air to the shut-o valve.

6. An automatic train stop comprising in combination, a maimreseryoir a train pipe, an engineers valve between the main reservoir and train pipe, a control valve arranged to be operated by a member on the trackway, a shut-off valve for closing the connection between the main reservoir and engineers valve, connections from thetrain pipe to the control valve and from the control valve to the shut-off valve for operating said shut-off valve when the control valve is actuated, a vent for said train pipe air opened by said shut-01f valve when the same is actuated by said train pipe air, an 'automatic cut-out valve interposed in the connections between the train pipe and control valve for rendering the control valve inoperative when the train pipe pressure is reduced by the manual control of the brakes,

and an automatic pressure controlling valve interposed at a point in the connections between the train pipe and shut-off valve.

7. An automatic train stop, comprising in combination with the main reservoir, train pipe and engineers valve of an air brake system, a shut-off valve controlling the communication between the main reservoir and engineers valve, a pressure operated device for actuating said shut-off valve, air connections between the train'pipe and said pressure actuated device, a control valve interposed in said connections and adapted to be operated by a member on the track-way, pressure operated mechanism for returning the controlvalve to its original condition, connections from the main reservoir to said pressure operated mechanism and valve mechanism under control of the shut-off valve for controlling flow from the main reservoir to said pressure operated 'mechanism.

8. An automatic train stop, comprising in combination with the main reservoir, train pipe and engineers valve of an air brake system, a shut-off valve controlling the communication between the main reservoir and engineers valve, a pressure operated device for actuating said shut-off valve, air connections between the train pipe and said pressure actuated device, a control valve interposed in said connections and adapted to be operated by a member on the track-way, pressure operated mechanism for returning the control valve to its original condition, connections from the main reservoir to said pressure operated mechanism, valve mecha nism under control of the shut-cit valve for controlling flow from the main reservoir to said pressure operated mechanism, a power controlling member and pressure actuated means for operating said power controlling member interposed in the air supply connections to the control. valve operating mecha nism.

9. In an automatic train stop, the combination with an air brake system including an engineers valve for controlling application of the brakes, of a shut-01f valve for rendering the engineers valve inoperative, a control valve connected to the tram pipe and operated by means on the trackway for operating said shut-ofl valve and effecting a service application of the brakes, and an emergency control valve for operating the shut-off valve and effecting an emergency application of the brakes.

10. In a system of the character descrlbed, the combination of a main reservoir, a train pipe, and an en'gineers valve mterposed between the reservoir and train pipe, a shutoff valve interposed between the reservoir and engineers valve, a control valve for admitting' air from the train pipe to the shutoff valve, and a compensating valve interposed between the train pipe and control valve having means for graduating the flow of air from the train pipe to said control valve.

11. In an automatic train stop, a train pipe and an engineers valve for normally controlling the application of the brakes, a valve for rendering the engineers valve 1neffective, a control valve for venting the train pipe to cause an application of the brakes, and an automatic compensating valve connected to the train pipe and control valve for regulating the rate of escape of air past said control valve.

12. In an automatic train stop, a train pipe and an engineers valve for normally controlling the application of the brakes a valve for rendering the engineers valve 1nefi'ective', a control valve for venting the train pipe to cause an application of the brakes, and a compensating valve interposed between the train pipe and control valve, said compensating valve having a valve member subjected to the train pipe pressure and governing the rate of flow of air to the control valve.

13. In an automatic train stop, a train pipe and an engineers valve for normally controlling the application of the brakes, a valve for rendering the engineers valve ineffective, a control valve for venting the train pipe to cause an application of the brakes, and a compensating valve interposed between the train pipe and control valve, said compensating valve having a pressure-operated member subjected to train pipe pressure provided with a restricted passage for controlling the flow of air to said control valve.

14. In an automatic train stop, a train pipe and an engineers valve for normally controlling the application of the brakes, a valve for rendering the engineers valve ineffective, a control valve for venting the train pipe to cause an application of the brakes, a cylinder in communication with said train pipe and having an outlet ort in communication with said control valve, a piston in said cylinder subjected to the train pipe pressure, and a slide carried by said piston covering the outlet port and provided with a diamond-shaped valve opening controlling said port.

15. In an automatic train stop, .a train pipe and an engineers valve for normally controlling the application of the brakes ,a valve for rendering the engineers valve ineffective, a control valve for venting the train plpe to cause an application of the brakes, a cylinder in communication with said train pipe and having an-outlet port in communication with said control valve, a piston in said cylinder subjected to the train pipe pressure, and a slide carried by said piston and controlling the outlet port.

'16. In combination with the train pipe of an air brake system, a compensating cylinder in communication with said train pipe and provided with an outlet port, a piston Working in the cylinder and subjected to the train pipe pressure, a slide carried by said piston and controlling the outlet port, and

an automatic cut-out valve interposed between the train pipe and the compensating valve provided with an operating member subjected to the train pipe pressure.

17. In combination with the main reservoir, a train pipe, and an engineers valve of an air brake system, a shut-off valve interposed between the reservoir and engineers valve, means for operating said shut-off valve, a train controlling member, pressure actuated means for operating said train controlling member, and valve mechanism under control of the shut-off valve for admitting air under pressure from the main reservoir to the pressure actuated means.

18. In an automatic train stopping system, a main shut-off valve for shutting off a source of fluid under pressure, a piston normally subjected to said fluid under pressure, and adapted to be cut off from said fluid upon actuation of the shut-off valve, train.

controlling means, a pressure actuated device for operating said train controlling means, and a valve operated by the piston aforesaid for controlling flow of actuating fluid from the supply aforesaid to the pressure actuated device.

19. In an automatic train stopping system, a main shut-off valve .for shutting off a source of fluid under pressure, a piston normally subjected to said fluid under pressure and adapted to be cut off from said fluld upon actuation of the shut-off valve, a train controlling means, a pressure actuated device for operating said train controlling means, a valve operated by the piston aforesaid for controlling flow of actuating fluid from the supply aforesaid to the pressure actu-' ated device, and means for automatlcally venting the pressure on said piston when the shut-off valve isclosed.

20. In an automatic train stopping system, a'main shut-off valve for shutting off a source of fluid under pressure, a piston normally subjected to said fluid under pressure and adapted to be out off from said fluid upon actuation of the shut-off valve, train controlling means, a pressure actuated device for operating said train controlling means, a valve operated by the piston aforesaid for controlling flow of actuating fluid from the supply aforesaid to the pressure actuated device, means for automatically venting the pressure on said piston when the shut-off valve is closed, and means for automatically venting the pressure beneath the piston when the shut-off valve is again opened.

21. In an automatic train stopping system, a shut-off valve having a supply passage therethrough, a valve member con trolling flow through said passage, a cylinder having a port open to said passage and controlled by said valve member, a piston in said cylinder, a supply valve operated by said piston, pressure actuated train controlling means, and fluid pressure supply connections controlled by the piston operated valve.

22. In an automatic train stopping system, a shut-off valve having a supply passage therethrough, a valve member controlling flow through said passage, a cylinder having a port open to said passage and controlled by said valve member, a piston in said cylinder, a supply valve operated by said piston, pressure actuated train controlling means, fluid pressure supply connections controlled by the piston operated valve and pressure actuated means for operating the shut-off valve.

23. In combination with a main reservoir, a train pipe and engineers valve, a shutofi' valve having a passage providing communication between the reservoir and engineers valve, a cylinder, a piston working in said cylinder, a valve carried by said piston and controlling the passage aforesaid, a vent in the cylinder controlled by the piston, a control valve connected with the train pipe, and air connections from said control valve to the head of the piston aforesaid.

24. In combination with a main reservoir, a train pipe and engineers valve, a shut-off valve having a passage providing communication between the reservoir and engineers valve, a cylinder, a piston working in said cylinder, a valve carried by said piston and controlling the passage aforesaid, a vent in the cylinder controlled by the piston, a control valve connected with the train pipe, air connections from said control valve to the head, of the piston aforesaid, restoring connections from the main reservoir to the control valve, and a supply valve in said connections under control of the shut-off control valve to the head of the piston aforesaid, restoring connections from the main reservoir to the'control valve, a supply valve in said connections under control of the shutofl valve, pressure actuated means for said supply valve, and venting connections from said pressure actuated device to the cylinder aforesaid controlled by the piston in said cylinder.

26. In combination with a main reservoir, a train pipe and engineers valve, a shut-off valve having a passage providing communication between the reservoir and engineers valve, a cylinder, a piston working in said cylinder, a valve carried by said piston and controlling the passage aforesaid, a vent in the cylinder controlled by the piston, a control valve connected with the train pipe, air connections from said control valve to the head of the piston aforesaid, and manually operable means for actuating the shut-off valve.

27. In an automatic train stop, a control valve, pressure actuated meansfor testing the control valve, fluid pressure supply connections thereto and a check valve interposed in said fluid pressure supply connec-. tions.

JOHN S. CRAWFORD. 

